Cleaning fluid for desludging internal-combustion engines



Patented June 12, 1951 'rr'r orr cc CLEANING FLUID FOR DESLUDGING I INTERNAL-COMBUSTION ENGINES William J. Ebel, White Plains, N. Y., assignor t Neil McEwen, Sr., Franklin Square, N. Y.

4 Claims.

This invention relates to improvements in the art of desludging internal combustion engines, including not only an improved desludging mixture, but also an improved process for producing a desludging mixture, and an improved method of using a desludging mixture in internal combustion engines and the like.

Among the objects of the present invention, it

is aimed to provide an improved method of desludging the crankcase and associated parts of an engine, such as an internal combustion engine, Diesel engine and the like, which will merely require removing the crankcase oil and introducing instead thereof an improved desludging mixture which will not only effectively desludge the interior of the crankcase and associated parts, but have a lubricating effect on the operative parts so that upon operation of the engine for a predetermined period of time there will result not only an effective desludging action, but also simultaneously an effective lubricating action onany operative parts brought into contact with the deslud ing mixture to protect the same from scufiin scarring, or injury of any kind.

More specifically, the present invention also aims to provide an improved desludging mixture characterized by a high lubricating value and film strength and also by a high solvency on sludge and other deposits formed in the crankcase and on associated parts of an engine as a result of use, which mixture can replace the crankcase oil, and then while the engine is operating, not only serve to lubricate the operating parts, but also effectively to desludge the interior. Still furthermore, the present invention also aims to provide an improved process for making a desludging mixture which will serve as a lubri- No Drawing. Application June 26, 1947, Serial No. 757,323

cant while the engine is operating and at the.

same time effectively desludge the interior.

The term sludge as herein used includes two general types, such as cold engine sludge and the hot engine sludge. The sludge in anengine is usually a mixture of both types in various proportions. This sludge is usually a mixture of water such as products of combustion, dirt such as earthy material, unburnt fuel, and oil, thickened with oxidation and thermal decomposition products plus metallic particles worn and scuifed from the sliding surfaces inthe cylinders and bearing areas. Although the formation and deposit of sludge in the crankcase and on the associated parts, the freezing or sticking of piston rings,-

pistons and valves, but may also coat or block the oil pump screens and thereby prevent the flow of oil to the bearings and operative parts with the consequent injury to the same, or else actually break or fracture the oil pump screen and permit the passage of objectionable matter to the bearings and operative parts with resulting injury.

This sludge takes the form-of a pasty or semisolid material with a consistency resembling soft mud, composed of a liquid mixed with other materials, some soluble and others insoluble, in the liquid, all thickening the liquid to various consistencies. The extremes in variation run from a soft ooze to a transparent lacquer glazing the piston skirt.

The oxidation products of the oil and the fuel vary over a wide range and include soft and hard oil-insoluble resins. Some of these resins are so dark, hard, and oil-insoluble that they resemble carbon or coke.

The oxidation products may also include water resulting from the burning of the fuel or oil, or both in the combustion chamber and lead salts resulting from the burning of tetraethyl lead When a leaded fuel was used.

The principal difference between hot engin sludge and cold engine sludge resides in the fact that hot engine sludge contains large amounts of resins resulting from the oxidation of the oil in the crankcase, but is relatively free from water and soot, while cold engine sludge is relatively free from resins resulting from the oxidation of the oil. Both types, however, contain leaded salts if leaded fuel was used.

Oil which contains dissolved oxygen or is exposed to oxygen in storage gradually forms I sludge. Furthermore, the sludges are not the same for different oils or for the same oil which has been subjected to different types and different degrees of refinement.

Still furthermore, there are sludges which are distinctly acid sludges, which are formed by the operative parts of an internal combustion engine,

Diesel engine and the like are well known, it may be well to point out that such sludge and deposits not only interfere with the operation of operating oxidation, condensation and polymerization of the more reactive hydrocarbons present in the refined oil. These sludges are viscous and brownish in color. One the other hand, there are sludges which consist of iron or copper salts of organic acids, the latter formed in service through asphalts, that is, on the basis of the solubility --char acteristics of various solvents.

The constituents of the sludge which are soluble in petroleum ether and not adsorbed from such solutions by fullers earth or other activated clays are classified as oils. The constituents of the sludge soluble in petroleum ether but removed from solution by adsorbents are classified as resins.

The constituents insoluble in petroleum ether but soluble in benzene are termed asphaltenes.

The constituents insoluble in benzene but sol-" uble in carbon disulfide are know-n.as-carbenea The constituents insoluble in all of: thesesol-s vents are known as carboids.

The term petroleum ether as here used;- cludes the lightest liquid fractions 'distilled'from petroleum, of an end boiling point not above"l75 F. The term benzene as here used refers to the aromatic hydrocarbon Cal-la, and does notemeant gasoline.

The preceding description covers .in general theslud'gesproduced in the lower section of the crankcase, namely on the oi1-screen,'inthe sump,

and adhering layers on the rods, wall .and pan. In' addition to the foregoing, there are alsolencountered deposits formed on the pistonskirt. :3 and ring groove area. A study of deposits..re--

moved from stuck'piston rings showedthem .to. be of a highly acidic nature. Extractionsby a solution of-four partsbenzene and onepart al-i cohol indicated "on titration these deposits con-i tain'acids'of a relatively high acid strength. i No specific identification has been made. of these' acidsexcept asAcids I, II, 1H,.and so on, idifiering'irom each other on thebasisof thedifferent solvents capable of holding them infisolution.

From thestudies made inpistonring-deposits, there is a basis for assumingthat the..lubricat=-- ing" oils oxidized to produce amongother-prod ucts, oxyacids, which because of a tendency-"to" condense chemically into insoluble deposits, 6011- stitute the source or. cause of. ring sticking.

In'lview of. .this heterogeneous nature of the.

sludgesrand deposits formed. in an internalcom-i bust'ion engine. and thelike, the removing of the.

same has heretofore constituted :a stubbornproblem. As an instance,- severalemethods have been-employed tosolve thisproblem, allaccom-zpanied with .fatal obiectionsfrom-la practical;

standpoint.

One method contemplated disassembling all oft-i theengine parts and dipping-themicinto a vat-- containing the particular cleaningliquid=-then-- produced.- The. cost of this method not only.

necessitated by the disassembling of the engine," cleaning..,operation andlreassembling of/the engine,. but also-bythe loss of usepfwthe vehicle while so beinggtreatedhmade this method uex-t tremely costly and impractical.

Another method contemplated adding axsma'll percentage of the cleaner selected-as an additive to the usual engine lubricating 'oil when the cleaning period extended from at least amonth to anindefinite period-, depending to a certain recognized that such flushing agent would have to possess a lubricating value in order to protect the operating parts of the engine while operating withthe flushing agent. All of the attempts with this third method "at solving'the problem,

4- however, seemed to have been blinded by the viewpoint that they required a hydrocarbon lubricating oil to impart a lubricating value to the flushing agent, and then only by the addition of a large amount of such lubricating oil frequently equalling up to ninety per cent by Volumeyof the flushing agent. However, lubricating oil substantially decreased the solvency properties of the cleaning fluid used and there- 'fore materially impaired, if it did not entirely destroy, thecleaning efiicacy of the cleaning fluid With the foregoing in mind, the present invention aimed in the first place tc'produce an improvedmethod of desludging engines by displacing the lubricating oil with the cleaning fluic without disassembling the engine, and operating the, engine for a comparatively short period of time, the cleaning fluid of which possessed a lubricating value imparted thereto not mainly, if atall, by a lubricating oil, but by a green soap or'the'like which did'not impair 'the'cleaning efiicacy of the cleaning fluid, and if anything, onlyweakened the same insignificantly.

With the foregoing in mind, it was still another object of the present invention to produce an improved cleaning mixture which had a range of boiling points so that during the cleaning operation the stripping oi'the lighter volatile constituents within the crankcase at a cleaning temperature of approximately F. would result in effecting a cleaning action'to otherwise inaccessible crankcase parts, such-as the valve compartments of. an L-head engine.- Furthermore, itwas, anobject to produce a composition possessing ,a mild alkalinity of the order;of pH 9'that is in no way corrosive to alloyed bearings or aluminum parts'but definitely effective on,acid sludges. ,Still furthermore, in order; to dissolve the gummy binder that causes piston ring. sticking, it .was an object of theinvention to permit the use of a cleaning fluid in quanti ties approximately doubling the quantity ofthe crankcase oil ordinarily required so that the flushingcleaner could pass up throughthe oil holesbehindthe oilcontrol .rings and reach the ringizone area, inturn to facilitate the cleaning fluidto splash up intov the interior of the piston and by ,virtue of its lightviscosity approximating thirty-five to forty seconds at 109F; to penetratel. the clearance space between the cylinder. walls" and the piston skirt.

In the prac ice of this, invention, excellent re ,sultshave beenachieved whenthe finalcleaning fiuid,.ldepending..upon the use, intended, consisted essentially in the following ExamplegI, when intended for use on heavy duty Diesel engines could consistto advantage of 17.0 parts by weight of soap 22.5 parts by weight of alcohol 30.5 parts by weight of ethylene dichloride 30.0 parts by weight of cresol.

Example ILiwhenintended for-use on heavy duty gasoline engines and heavy duty Diesel en-v gines could consist-of 13.0.parts by weight of soap 2l.0 partsby weight of alcohol,

32.0. parts by weight ofv ethylene dichloride; 26.0,parts by weight of cresol.:

Example III, intended foruseon the engines of passenger cars and small package cars of a capacityof three-fourths to one and one-half tons,

where the motor has been used for more than thirty thousand miles, could consist of 15.6 parts by weight of soap 20.3 parts by weight of alcohol 27.9 parts by weight of ethylene dichloride 26.8 parts by weight of cresol 10.4 parts by weight of naphtha.

16.0 parts by weight of soap 21.0 parts by weight of alcohol 28.0 parts by weight of ethylene dichloride 24.0 parts by weight of cresol 11.0 parts by weight of naphtha.

In the aforesaid examples, the soap is preferably of the type known as green soap consisting essentially of linseed oil, soy bean oil, and the like vegetable oil, saponified by potash with no additional detergents, the soap being preferably of a plastic of semi-solid consistency.

The alcohol selected is preferably isopropyl alcohol; the cresol selected is preferably of the type characterized as 2 metaparacresol containing approximately fifty-nine per cent metacre'sol; and the naphtha employed is preferably of the high flash type having a distillation range from 300 F. up to 400 F.

In the aforesaid examples, the soap is added to provide the necessary film strength to prevent scuffing and seizing of the rubbing parts. One possible additional purpose is to maintain the proper alkalinity expressed as a pH value of 9. The isopropyl alcohol acts primarily as a vehicle to hold the soap and as a solvent for the alcohol soluble resins of the sludge. Certain of the oxyacide identified in the lacquers that coat the piston skirt ring zone areas also dissolve in the alcohol. The ethylene dichloride, on the other hand, serves as a solvent for otherresins in the piston lacquer and sludge that are insoluble in the alcohol. Under present conditions of analyses, the oxyacids in the piston lacquer have been identified as Acids I, II and III, soluble in different solvents. Acid I,-soluble in alcohol by extraction releases a residue that upon saponification with potash and filtration can be extracted with ether or ethylene dichloride to dissolve Acids II and III. The cresol, on the other hand, is a powerful solvent for those insoluble tarry deposits that are not soluble in the aforesaid solvents. Cresol, in turn, present in coal tar, can become a tar solvent. Extensive experimentation has conclusively proved that diminishing the proportions of cresol from those specified in the several examples results in the partially cleansed engine crankcase interiors, especially when the sludge is of the hard baked type of long duration on the oil screen and in the ring zone.

The naphtha serves primarily as an extender and as a solvent for desludging resins occurring in the crankcase sludge on the piston.

The solvency "of the various ingredients aforesaid necessarily overlap to some extent, but the absence of any one of the ingredients becomes immediately noticeable both in the thoroughness and speed of the desludging process.

The naphtha is also used to decrease the cost, serving to a certain extent to replace some of the other more expensive ingredients. On the other 6 hand, when the mixture is to be transported great distances, in the interest of package economy, the naphtha is preferably eliminated. In other words, the transportation cost in such instances would more than make up the difference in cost between the naphtha and the more expensive ingredients.

In general, the cleaning fluid consists essentially of a mixture of about 15 to 18 parts by weight of green soap of a semi-solid consistency composed of a'potash saponified vegetable oil of the group consisting of linseed oil and soy bean oil, about 20 to 24 parts by weight of isopropyl alcohol, about 27 to 32 parts by weight of ethylene dichloride, and about 24 to 30 parts by weight of cresol. In turn, for some purposes there may be added to the mixture about 10 to 11 parts by weight of a high flash naphtha having a distillation range from 300 F. up to 400 F.

The process of making this mixture also presents certain advantages and is considered novel and important. The process consists essentially in dissolving about 15 to 18' parts by weight of the green soap of a semi-solid consistency composed of a potash saponified vegetable oil in about 20 to 24 parts by weight of the isopropyl alcohol when heating the same to a temperature of F. and allowing the same to continue for about 45 minutes, until the temperature reaches approximately 140 F. Throughout this heat treatment, the mixture is agitated. After reaching the temperature of about 140 F., about 27 to 32 parts by weight of the ethylene dichloride is added which will immediately lower the temperature to about F., and materially reduce vaporization losses. After the ethylene dichloride has been effectively stirred into the mixture, then about 24 to 30 parts by weight of the cresol and about 10 to 11 parts by Weight of the naphtha are added in the order named while maintaining agitation. The complete mixing process for a quantity of one thousand pounds should not exceed one and one-half hours.

Obviously the aforesaid mixture will omit the addition of the naphtha when it is to be eliminated to produce Examples I and II, aforesaid.

The method of using the aforesaid mixture in desludging an engine is also believed to be new and important. Excellent results have been achieved when a mixture, such as outlined in Examples I to IV, inclusive, were selected as the cleansing liquid and introduced into the crankcase of the internal combustion engine after draining the used lubricating oil. The quantity of cleaning liquid, however, was approximately twice as much as the lubricating oil ordinarily used. Thereupon the motor was initially run for at least one hour with the idling speeds set to anything below 1000 R. P. M., but preferably not lower than 750 R. P. M. With a six cylinder valve in head 90 H. P. engine, theretofore used in hard fast driving, after an hours run as aforesaid set for an idling speed of 750 R. P. M., it was found that the engine had increased in idling speed to approximately 1200 R. P. M. In place of this method, after the mixture has been introduced into the crank case, excellent results have also been achieved when the motor was initially run for only ten minutes at an idlin speed between 750 and 1000 R. P. M., the ignition then shut off and the motor and cleaner allowed to stand for one hour, and then the motor again operated for a period of about one hour set at a speed of between 750 and 1000 75 R. P. M.

It has alsobeen found that the soap can be reduced in quantity with a small amount of lubricating oil to supplement the lubricating function of the soap, but that when the lubricating oil exceeded ten per cent by weight of the entire mixture, the cleanin efiiciency was materially affected.

It is obvious that various changes and modifications may be made to the steps in the method of operation, to the steps in the process of making the mixture, and to the percentages of the ingredients without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. A cleaning fluid for desludging internal combustion engines while operating, consisting essentially of a mixture of about to 18 parts by wei ht of green soap of a semi-solid consistency composed of a potash saponified vegetable oil of the group consisting of lineseed oil and soy bean oil, about to 24 parts by weight of isopropyl alcohol, about '7 to 32 parts by weight of ethylene dichloride, and about 24 to parts by weight of cresol.

2. A cleaning fluid consisting essentially of the mixture set forth in claim 1 and of about 10 to 11 parts by weight of a high flash naphtha having a distillation range from 300 F. to 400 F.

3. The process of making a cleaning fluid for desludging internal combustion engines while operating, consisting essentially in mixing and agitatin about 15 to 18 parts weight of green soap of a semi-solid consistency composed of a potash saponified vegetable oil of the group consisting of linseed oil and soy bean oil, with about 20 to 24 parts by weight of isopropyl alcohol, heating the mixture to a temperature of about and thereupon increasing the temperature to about 140 ,F., thereupon adding about 27 to 32 parts by weight of ethylene dichloride and reducin the temperature to about F., and thereuponadding about 24 to 30 parts by weightof cresol-while continuing the agitation. l

4. The process asset forth in claim 3 characterized by adding simultaneously with the cresol about 10 to 11 parts by weight of a high flash naphtha having a distillation range from,

300 F. to 400 F. while continuing the agitatio W L .LIAM J. EBEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,128,685 Yates Aug. 30, 1938 2,251,988 Curran Aug. 12, 1941 2,279,001 Matheson et al. Apr. 7, 1942 2,386,789 Gregg Oct. 16, 1945 2,410,613 Ruthrufi Nov. 5, 1946 OTHER REFERENCES Chemical Formulary, Bennett, volume 4 (1939), pages 491-492. 

1. A CLEANING FLUID FOR DESLUDGING INTERNAL COMBUSTION ENGINES WHILE OPERATING, CONSISTING ESSENTIALLY OF A MIXTURE OF ABOUT 15 TO 18 PARTS BY WEIGHT OF GREEN SOAP OF A SEMI-SOLID CONSISTENCY COMPOSED OF A POTASH SAPONIFIED VEGETABLE OIL OF THE GROUP CONSISTING OF LINESEED OIL AND SOY BEAN OIL, ABOUT 20 TO 24 PARTS BY WEIGHT OF ISOPROPYL ALCOHOL, ABOUT 27 TO 32 PARTS BY WEIGHT OF ETHYLENE DICHLORIDE, AND ABOUT 24 TO 30 PARTS BY WEIGHT OF CRESCOL. 